Studies Of High-throughput Screening And Determination Platform For Veterinary Residues In Food And Diary Exposure Assessment

In recent years, food safety accidents have exploded in China and abroad. Food safety has become a major concern of the whole society. All these accidents expose that great hazard is threatening people’s health, such as strictly regulated veterinary drugs substituted by new alternative drug, drugs of different categories with different effects feeded at the same time, multi-residues of veterinary drugs appeared in the animal derived food. The objective of this paper is to study the food safety problem by analyzing veterinary residues in food and dietary exposure assessment, providing a new sight for analysis and evaluation of food safety issues caused by veterinary residues.In the first chapter, it mainly describes the current situation and main sources of food safety problem in China, and discusses the challenges for food safety under the new situation.Several concepts related to food safety are also introduced. The principal methods for detection of veterinary residues in food are reviewed. The purposes and methods of this study are also introduced in this chapter.In the second chapter, a high-throughput screening method for73veterinary residues in pork was developed, containing β-agonists, sedatives and sulfonamides. The method was established by high performance liquid chromatography hybrid-quadruple time-of-flight mass spectrometry (HPLC-Q-TOF-MS). These samples were extracted and purified by dispersed solid-phase extraction, then analyzed by HPLC-Q-TOF-MS and quantitated with isotope internal standard. The method was proved to be rapid and simple, with high selectivity and sensitivity. The result showed that the method could be used for both targeted and untargeted veterinary residues in pork. In the third chapter, a platform for detecting antiviral drugs in livestock and poultry meats was established, including the determination of amantadine in poultry meats and the determination of ribavirin in poultry and livestock meats. The samples were extracted by mixed solvent with or without enzymolysis respectively, purified by solid phase extraction, then determined by linear ion trap with liquid chromatography tandem quadrupole mass spectrometry (QTrap), and quantified by using isotope internal standard method. These two determination methods were both validated. The linear correlation coefficient of peak area and concentration was above0.999, all of the average recoveries were above80%. The platform was proved to be used as a routine method for antiviral drugs determination in poultry and pork meats.In the fourth chapter, a high-throughput LC-MS/MS method for simultaneous detection of20β-agnoists in poultry and pork meat was developed. The samples were extracted by mixed solvent with enzymolysis, purified by SPE, determined by LC-MS/MS, and quantified by using isotope internal standard method or external standard method. The validation indicated that that the method was suitable for the determination of β-agnoist in poultry and pork.The dietary exposure assessment of ractopamine residue in pork meats and livers was studied by using the established LC-MS/MS method as well as statistical analysis. The risk assessment included hazard identification, hazard characterization, exposure assessment, risk assessment and risk characterization. The assessment result showed that ractopamine residue in pork food was at a low risk for human health.In the fifth chapter, a rapid LC-MS/MS method for detection of chloramphenicol (CAP) in poultry meat was developed. The samples were extracted by acetonitrile (ACN), purified by hexane, determined by LC-MS/MS with a concentrated analyte, and quantified by using isotope internal standard method. The validation of the method showed that the method was suitable for the determination of CAP in poultry meat.The dietary exposure assessment of CAP residue in poultry is studied. The risk assessment included hazard identification, hazard characterization, exposure assessment, risk assessment and risk characterization. The assessment result suggested that CAP residues in poultry meat was at low risk of carcinogenicity for human, and the adverse clinical reaction caused by CAP would occur less likely.